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arXiv · 1211.6167

In-plane antiferromagnetism in $Na_{0.5}CoO_2$ induced by $Sb_{Co}$ dopants

M. H. N. Assadi·S. Li·R. K. Zheng·S. P. Ringer·A. B. Yu
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Abstract

$Na_xCoO_2$ has a fascinating and complex magnetic phase diagram that can be further manipulated by doping. Here, we investigated the effect of electron doping on the magnetic coupling among $Co^{4+}$ ions in $Na_xCoO_2$ using density functional theory based on Hartree-Fock hybrid functional. We found that electron doping through substitutional $Sb_{Co}$ dopants flip the in-plane ferromagnetic coupling among $Co^{4+}$ ions in the undoped compound to antiferromagnetic. Electron doping through interstitial $Cu_{Int}$, however, does not have a similar effect as $Cu_{Int}$ dopant leaves the compound ferromagnetic, just like the case of the undoped compound. The results demonstrate the critical dependence of magnetic phase in $Na_{0.5}CoO_2$ on the dopant and its incorporation site.

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M. H. N. Assadi, S. Li, R. K. Zheng, S. P. Ringer, A. B. Yu. 2012-11-26. In-plane antiferromagnetism in $Na_{0.5}CoO_2$ induced by $Sb_{Co}$ dopants. https://arxiv.org/abs/1211.6167

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